Hello to all,
I am just passing on my experience with the defective update issue. I provide IT support services in Miami, FL USA. I have for the last several years recommended to home users the Avast anti-virus software without any hesitation and will, for most users, continue to do so. I also have several business clients running the Pro version or SBS packages. Across a base of a couple hundred PCs I have so far experienced issues with 12 computers, mostly home users. It seems that if they were actively using the computer during the time window that the errant detection file was in place they had a much higher likelihood of messing things up by deleting files that were flagged. Since Avast's default is to prompt the user to select an action - most end-users pick 'delete' it seems. Oddly enough, in all nearly all cases my users experienced problem that made their computers unusable - but easily correctable. Most could not work when booting normally and logging in as themselves or as local administrator (yes, all of my home PC users have a separate admin account even on XP). It seems various programs that drop tray icons never load and on first use of IE or Windows Explorer the PC would become unresponsive and require a hard poweroff. Booting into Safe Mode and uninstalling Avast corrected the lockup/performance problem in every case - 10 on XP and 1 on Vista. In all cases where I had the chance to do a remote session prior to the uninstall in safe mode (only 5 of them) there were no files in the chest but most reported having deleted something. In all cases the computers continued to behave properly - at some point I imagine I may run into a problem with a specific program like Spybot or Adobe reader, where something my have to be reinstalled. Avast can be reinstalled afterward works without issue as well.
While this problem was obviously quite nasty I believe that Alwil's response has been good and that they are serious about reducing the probability of it happening again. Compared to McAfee's massive, at least once a year screw ups I would give Avast the nod on reliability and still highly recommend it.
I hope this information is useful to someone that may still be struggling with a PC that is not behaving properly after being affected by the issue.
Regards,
-felipe
